<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="UTF-8" />
    <meta http-equiv="X-UA-Compatible" content="IE=edge" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <title>Document</title>
  </head>
  <body>
    <script>
      function login(username, password, callback) {
        setTimeout(() => {
          if (username === 'zs' && password === '123') {
            callback('登录成功')
          } else {
            callback('登陆失败')
          }
        }, 100)
      }

      login('s', '123', (res) => {
        console.log(res)
      })
    </script>
  </body>
</html>
